A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 2925-01-121-3355
NSN 5905-01-151-1194
NSN 4140-01-212-8286
NSN 5920-00-655-1154
NSN 5905-01-115-8808
NSN 6610-00-951-4451
NSN 5985-01-028-0015
NSN 6610-01-574-0050
NSN 5930-01-557-1591
NSN 5925-01-161-9564
NSN 5930-01-485-3368
NSN 5905-00-948-7833